Field of the Invention
The disclosure relates to an electronic device. More specifically, the disclosure relates to an electronic device in which a plug-in module, which includes a printed substrate on which an electronic circuit is mounted, is detachably connected to a terminal board disposed on a baseplate.
Priorities are claimed on Japanese Patent Application No. 2014-014666, filed Jan. 29, 2014, and Japanese Patent Application No. 2014-190617, filed Sep. 19, 2014, the contents of which are incorporated herein by reference.
Description of Related Art
As a type of an electronic device, there is a device in which a plurality of plug-in modules, which include a printed substrate on which an electronic circuit is mounted, is detachably connected to a terminal board disposed on a baseplate.
FIG. 11 is a drawing illustrating an example of a control system including the electronic device. As shown in FIG. 11, a field control station 10 communicates with various types of computers such as a remote operation monitoring server, a human interface station, an SMTP (Simple Mail Transfer Protocol) server, an engineering station, a safety control station, an advanced process control station, an integration gateway station, and a general-purpose subsystem gateway. The field control station 10 is detachably connected to a first terminal board in which input-output modules 11 and various types of function modules 12 are disposed on a baseplate (not shown). For example, the function modules 12 are such as a control module which controls transmitting/receiving various types of signals to/from a host system and an electrical power supply module.
The field control station 10 is connected to a second terminal board 30 with a cable 20. For example, a connector 31 to which the cable 20 of a system side is detachably connected, a terminal block 32 to which a cable of a field side is connected, and a disconnecting member 33 are disposed on the second terminal board 30. The terminal block 32 is connected to a field device (for example, a sensing device, a motor, and a valve) with the cable of the field side. The disconnecting member 33 mechanically disconnects, if needed, a signal connection between the connector 31 and the terminal block 32.
FIG. 12 is a drawing illustrating the second terminal board 30. FIG. 13 is a circuit block diagram of the second terminal board 30. In the second terminal board 30, for example, a wiring member which is capable of being inserted and ejected with a connector is used as the disconnecting member 33.
For example, when the system is started-up or the system is maintained, the disconnecting member 33 checks a state of the signal connections of the system side and a state of the signal connections of the field side individually. The signal input-output connection between the system side and the field side is disconnected mechanically by ejecting the disconnecting member 33 from the second terminal board 30.
The fuse 34 fuses to protect the signal connection when a large current which is more than a predetermined current flows. The fuse 34 is series-connected to the disconnecting member 33. In addition to these components, if needed, auxiliary components such as a relay and an LED (Light Emitting Diode) are mounted on the second terminal board 30.
The circuit of the second terminal board 30 is divided into a left block and a right block. Channels 1 through 16 are disposed in the left block. Channels 17 through 32 are disposed in the right block. A series circuit which is equipped with the disconnecting member 33 and the fuse 34 is disposed in each of the channels. The disconnecting members 33a and the fuses 34a are disposed in the channel 1 through 16. The disconnecting members 33b and the fuses 34b are disposed in the channel 17 through 32.
A duplexed electrical power supply block 35 for driving the left block and the right block is disposed under the left block and the right block.
Also, as shown in FIG. 14A through FIG. 14E, there are electronic devices which are terminal blocks separated from the second terminal board 30. An electronic device 141 shown in FIG. 14A, an electronic device 142 shown in FIG. 14B, and an electronic device 143 shown in FIG. 14C are disconnecting terminal blocks mounted on a DIN (Deutsche Industrie Normen) rail. An electronic device 144 shown in FIG. 14D and an electronic device 145 shown in FIG. 14E are relay terminal blocks mounted on a terminal board.
In Japanese Unexamined Patent Application Publication No. 2012-134352, a terminal board, which can be fixed on a DIN rail in a small space without sliding laterally, is described. A substrate of the terminal board can be stored in a metallic case.
However, conventionally, the field control station 10, which is equipped with the input-output modules 11 and the function modules 12, and the second terminal board 30, which is equipped with the disconnecting member 33 and the fuse 34, are separated. For the reason, in a case of an operation check when establishing a system or in a case of a maintenance check after establishing the system, a measurement check should be performed by selecting the signal connections of the channels of the field control station 10 and the second terminal board 30 and checking the selected signal connections. Therefore, there is a problem that the work is complicated. Especially, in a case of a large-scale system having many channels, man-hour of the work is to be much more.
Also, because the field control station 10 and the second terminal board 30 are separated with each other, there is a problem of increasing a number of components and assembly time and increasing costs.
Also, in a case where the control system is established by using the field control station 10 and the second terminal board 30, there is a problem that a space for disposing the field control station 10 and the second terminal board 30 is needed.
Further, because the field control station 10 and the second terminal board 30 are connected with the cable 20, in a case of a large-scale system having many control objects, there is a problem that cables are congested and the works such as a control system establishment and a maintenance check are complicated.